New millisecond pulsar discovered

Using the Green Bank Telescope (GBT), astronomers have observed a globular cluster known as Terzan 6. They have detected a new millisecond pulsar that is likely associated with the cluster. The discovery was reported in a research paper published September 17 on the preprint server arXiv.

Pulsars are rotating, highly magnetized neutron stars that emit a beam of electromagnetic radiation. The fastest rotating pulsars, with rotation periods of less than 30 milliseconds, are called millisecond pulsars (MSPs). Astronomers assume that they form in binary systems when the initially more massive component transforms into a neutron star that is then set into rotation due to the accretion of material from the secondary star.

Terzan 6 is a metal-rich, collapsed galactic globular cluster located about 21,800 light-years from Earth. Although the cluster has been known for decades, no pulsars have been detected there until now. However, its high rate of stellar encounters suggests that it could host dozens of such objects.

Today, a team of astronomers led by Shi-Jie Gao of Nanjing University in China reports the detection of a new MSP, which may be the first known pulsar in Terzan 6. The discovery is the result of a targeted search of this cluster with the C-band GBT (4-8 GHz).

“Here we report the discovery of a 5.33 ms pulsar associated with Terzan 6, designated PSR J1751–3116A,” the researchers wrote.

As stated in the article, the PSR J1751–3116A has a rotation period of approximately 5.33 milliseconds, while its dispersion measurement is approximately 383.08 pc/cm^-3The obtained dispersion measurement strongly supports the association between PSR J1751–3116A and Terzan 6.

The study found that the flux density of the pulsar PSR J1751–3116A at 6.0 GHz is 3.0 µJy. Assuming a spectral index of −1.4, the astronomers estimated that the flux density of the pulsar at 1.44 GHz is about 23 µJy.

The authors of the paper assume that PSR J1751–3116A is an isolated millisecond pulsar, which is consistent with the classification of Terzan 6 as a core-collapsed cluster. They note that PSR J1751–3116A potentially formed through dynamical interactions.

Summarizing the results, the researchers note that they hope for further discoveries of pulsars in Terzan 6 through the use of existing radio telescopes at higher frequencies.

“Given the exceptionally high stellar encounter rate, more sensitive searches such as using GBT and MeerKAT (e.g., TRAPUM, a large MeerKAT survey project) should result in new pulsar discoveries in Terzan 6,” the scientists conclude.

© 2024 Science X Network